7 12y 1 4 2y 5 3 July 8, 2019 16 32 64 128 4 7y-(2 5y+12 4)=1 9 (7y - 1)/12 - (y + 1)/4 = 2y+5 3 * 3) 4) (7y - 1)/12 - (y + 1)/4 = 2y+5 3 * (2 - 7y)/6 + (4y + 7)/3 = - y/2 4 7-(2 5y+12 4)=1 9